Atypical foveomacular vitelliform degeneration, adult type.

Foveomacular vitelliform degeneration, adult type (FVDAT) is a disciform, macular degeneration that is usually encountered in the fifth to seventh decade of life. It appears ophthalmoscopically similar to the vitelliform or "egg-yolk" stage of Best's disease (vitelliform degeneration), but shows no inheritance pattern. Electrooculographic (EOG) testing reveals a normal or only slightly reduced Arden ratio (light peak/dark trough). The prognosis is optimistic, as most patients retain reading vision throughout life. This case report describes an atypical case in which the signs and symptoms of FVDAT are not exactly those regularly seen. However, it does closely resemble the disease sufficiently to warrant this diagnosis.